Katsutomo Tsujii

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PURPOSE To develop an infrastructure for the integrated Monte Carlo verification system (MCVS) to verify the accuracy of conventional dose calculations, which often fail to accurately predict dose distributions, mainly due to inhomogeneities in the patient's anatomy, for example, in lung and bone. METHODS AND MATERIALS The MCVS consists of the graphical(More)
PURPOSE To evaluate setup error and interfractional changes in tumor motion magnitude using an electric portal imaging device in cine mode (EPID cine) during the course of stereotactic body radiation therapy (SBRT) for non-small-cell lung cancer (NSCLC) and to calculate margins to compensate for these variations. MATERIALS AND METHODS Subjects were 28(More)
PURPOSE To determine whether maximum or average intensity projection (MIP or AIP, respectively) reconstructed from 4-dimensional computed tomography (4DCT) is preferred for alignment to cone beam CT (CBCT) images in lung stereotactic body radiation therapy. METHODS AND MATERIALS Stationary CT and 4DCT images were acquired with a target phantom at the(More)
The aim of this study was to compare three strategies for intensity-modulated radiotherapy (IMRT) for 20 head-and-neck cancer patients. For simultaneous integrated boost (SIB), doses were 66 and 54 Gy in 30 fractions for PTVboost and PTVelective, respectively. Two-phase IMRT delivered 50 Gy in 25 fractions to PTVelective in the First Plan, and 20 Gy in 10(More)
OBJECTIVE To examine the correlation between the patient rotational error measured with pulmonary point registration and tumor shift after bony anatomy matching in stereotactic body radiotherapy for lung cancer. METHODS Twenty-six patients with lung cancer who underwent stereotactic body radiotherapy were the subjects. On 104 cone-beam computed tomography(More)
There are 2 methods commonly used for patient positioning in the anterior-posterior (A-P) direction: one is the skin mark patient setup method (SMPS) and the other is the couch height-based patient setup method (CHPS). This study compared the setup accuracy of these 2 methods for abdominal radiation therapy. The enrollment for this study comprised 23(More)
PURPOSE The quality assurance (QA) system that simultaneously quantifies the position and duration of an (192)Ir source (dwell position and time) was developed and the performance of this system was evaluated in high-dose-rate brachytherapy. METHODS This QA system has two functions to verify and quantify dwell position and time by using a web camera. The(More)
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